As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE "VTK" "MAP" DISPLAYED ON CAPT ND. SIMULTANOUSLY "LDG ALT" DISPLAYED ON CAPT PFD. PROCEDURE FOR LEFT FMC FAILURE FOLLOWED. GROUNDED - YES. PERFORMED FMC BITE REF FIM 34-61 TASK 801. FOUND NO CURRENT FAULTS OF SENSORS. THIS FMC LOGGED A "PGM FAULT" ON 08 SEP18. T/S PER FIM 34-61 TASK 807, REF PARA A(4) "DO NOT REPLACE THE FMC. IF THE ONLY MSG IS PGM FAULT." COMPLETED TEST OF L-FMC, AND FMC PROMPT SHOWS ON MCDU.